Densities and Partial Molar Volumes of Dodecyltrimethylammonium Bromide in Binary Systems (Methanol+Water) at T=(298.15 to 323.15) K

摘要

The densities of dodecyltrimethylammonium bromide in pure water and in methanol + water mixed solvent media containing (0.10, 0.20, 0.30, and 0.40) volume fractions of methanol were measured at (298.15, 308.15, 318.15, and 323.15) K. The concentrations are varied from (0.4 ?10-1 to 1.2 ?10-1) mol kg-1. The results showed almost increase on the densities with increasing surfactant concentration. Also, the densities are found to decrease with increasing temperature over the entire concentration range investigated in a given mixed solvent medium and these values are found to decrease with increasing methanol content in the solvent composition. The effects of concentration, solvent composition and temperature on the partial molar volumes are discussed.